Dump trucks have become a mainstay in the automotive market for agricultural, commercial, landscaping and other uses. Generally, these dump trucks are large heavy-duty trucks with heavy-duty hydraulics systems for lifting the relatively heavy metal truck box beds. The lifting and tipping systems not only have to lift the truck box itself but it must also lift the contents of the box as well.
Since the automotive industry has been trying to reduce the weight of their vehicles, they have been looking at plastic pick-up boxes, as they are much lighter in weight than a traditional steel metal pick-up truck boxes. One type of pick-up truck box made of plastic is made by a powder molding technology owned by 3DM Technologies, Inc., of Troy, Mich. The pick-up truck box made by their process is approximately 100 pounds less than a standard metal pick-up truck box, lending itself to a much simpler method and mechanism for affecting a dump truck tipping mechanism. By powder molding the truck box itself, stanchion supports and other metallic inserts can be molded directly into the pick-up truck box, acting as connecting and attachment points for the hydraulic dumping mechanism.
It is an object of the present invention to utilize the reduced weight and singular component truck box bed created by the use of new powder molded technology for making a light weight, easily lifted, one piece plastic body. The PCT International Patent Application Ser. No. PCT/US02/03298 for the invention entitled “Processes For Forming Plastic, Apparatuses For Forming Plastic, And Articles Made Therefrom”, also owned by the present owners of this application, is incorporated herein by reference. U.S. Provisional Patent Application No. 60/414,969 is also incorporated herein by reference.
Therefore, it is an object of the present invention to provide a lightweight dump truck for use on street grade, light-duty pick-up trucks, without having the need to purchase a special heavy-duty truck. Also, as the truck box is made by the new powder mold technology described above, the payload capacity has increased, thereby making the dump truck tipping mechanism more desirable. The present invention provides these objects and advantages and also provides a tailgate construction which can reach down to the ground such that a normal size light-duty pick-up truck can be utilized for running various tools and equipment directly up the tailgate into the bed of the truck, allowing the use of heavy duty wheelchairs, recreational vehicles such as ATVs and motorcycles, as well as the loading of small livestock, including dogs and the like.